Mockingbirds show heightened aggression after lead exposure | Hacker News Reader

Mockingbirds show heightened aggression after lead exposure

eurekalert.org

88 pointscurtis27 comments

See also the Lead-Crime hypothesis, which proposes a causal relationship between the banning of leaded petrol and a sharp decline in crime rates:

[0] https://ichef.bbci.co.uk/news/624/media/images/74298000/gif/...

[1] https://www.bbc.com/news/magazine-27067615

Leaded petrol was made possible by Thomas Midgley, who also discovered Freon resulting in CFCs and the ozone hole.

The article touches on that:

> Sub-lethal exposure to lead in humans has been linked to increased aggression, with people who grow up in high-lead neighborhoods having a higher probability to be incarcerated for violent crime. They also tend to score lower in standardized tests.

Wasn't this kind of debunked?

No. The general conclusion seems to be that lead wasn't the only thing related to the decline of violent crime in the US but it was probably a significant factor.

The evidence is not only from the US. It's from all over the world. Different developed countries have moved to unleaded different times and their violent crime rates decline as well.

In a similar vein, the presence of lithium in drinking water has been shown to reduce violent crime, as well as general cognitive disorders [1][2].

[1] https://www.ncbi.nlm.nih.gov/pubmed/1699579

[2] https://www.ncbi.nlm.nih.gov/pubmed/24919696

Imho the whole history around TEL [0] is a pretty sad example of human hubris and our tendency to underestimate the negative impacts of our actions.

[0] https://en.wikipedia.org/wiki/Tetraethyllead#Controversy_and...

Less about human hubris and more about the single drive to maximise profit to the detriment of any other considerations. My favourite part:

By 2000, the TEL industry had moved the major portion of their sales to developing countries whose governments they lobbied against phasing out leaded gasoline.

Monsters.

It is always weird to me how people refer to these people as monsters, but do very little to stop their actions, and seem to actively support them if it makes their life even slightly easier. Classifying the people who make these decisions as monsters is stupid, because it somwhow makes them seem outliers from the average human moral conduct. They aren't outliers. That is just simply how most humans are or become when they are given a large amount of power.

If we want real change we are going to have to realize that 99.9% of humans are lazy, selfish, and err on the side of evil.

The top infrastructure priority in the entire United States should be to remove all lead pipes. It would cost a lot but it would have an enormous effect on health and reduce crime/violence.

It would also result in a very large number of jobs.

Where I come from, the advice is to just leave them as a protective layer has formed on the inside of the pipes through oxidation.

Where I come from, the main problem isn't the lead pipes, it's the lead solder used on the lead pipes.

Where I come from, the solder is not much of a problem. We paid everyone a ton of money to replace their pipes, leaving only solder and fittings as lead sources, and we have very little lead in our water to speak of.

https://www.npr.org/2016/03/31/472567733/avoiding-a-future-c...

Where I come from

https://www.npr.org/2016/03/16/470512927/before-flint-lead-c...

It's a CaCO3 layer that keeps lead out of solution by raising pH.

The paper http://karubian.tulane.edu/wp-content/uploads/sites/9/2018/1...

Always have to throw this in there when I see articles about lead exposure:

Tetraethyl lead (TEL) is still being manufactured in the UK, and being sold in a handful of countries for consumer gasoline use. One company in the world manufactures the material. It's an easy lookup. They've openly said they won't stop manufacturing the material until they're forced to by government intervention.

Leaded fuel is still being used in aviation as well, even in countries where it has been banned for road use. The primary aircraft that require leaded fuel are small, personal use aircraft. You're being poisoned so some rich bastards can play in their toys.

there probably arent enough rich bastards in small planes to poison those of us in the same countries as them

The statement regarding lead pollution is exactly true. If the usage of lead is reduced and stopped(which is not possible though) then everything will fall in its place.

I find Lead-crime hypothesis interesting, as well as increased policing, mass urbanization, blue collar office work.

But I also find several other reasons who might explain fall of aggression: Abundance of porn! TV/Computers/Internet/Smartphones enabled more porn in aggressive male population. If I'm right, then we must see lowered testosterone levels in male population and Less change of aggression in females in the same period. Or check if lead hypothesis enabled females to have same level of lower aggression.

What's with the uptick in certain areas? Do they still use leaded gas in Baltimore and Chicago?

Poorer urban areas tend to have a lot of older properties with flaky, poorly maintained paint jobs that often include several old layers of leaded paint in them.

Better-off areas have long since been mitigated or can afford to maintain their buildings to prevent chips from lying around.

No one claims lead is the only factor explaining crime rates.

Well, the article at hand is about mockingbirds... So I'm not sure how any of your theories are relevant to the article at hand.

I love HNs little obsessions. Lead causing aggression is one of them. I feel like I've seen links about it for years, and I'm not sure I've clicked a single one of them.

It's not something that originated here. These hypotheses are based on correlation. That does not imply causation though.

Disclaimer: my educated guess is that there is probably a real connection between lead and functioning of nervous system. Element particles/molecules probably have very high ability to diffuse through complex systems due to their small particle sizes.

Reply on news.ycombinator.com